Thermoelectric Module And Flexible Thermoelectric Circuit Assembly
A thermoelectric module has a base and first and second thermoelectric elements set in the base and electrically isolated by the base. A bottom layer is coupled to a bottom surface of the base, a bottom surface of the first thermoelectric element, and a bottom surface of the second thermoelectric element to electrically connect the first and second thermoelectric elements. The base is used to protect the thermoelectric elements. Multiple thermoelectric modules may be mounted to and connected by conductors on a flexible circuit panel to create a flexible thermoelectric circuit assembly for cooling, heating and/or power generating applications.
This application claims priority to U.S. provisional patent application No. 62/456,346, filed Feb. 8, 2017.
TECHNICAL FIELDExample embodiments relate to a discrete thermoelectric module and a flexible thermoelectric circuit assembly incorporating the discrete thermoelectric modules. The thermoelectric module and flexible thermoelectric circuit assembly may be used for various cooling, heating and/or power generating applications.
BACKGROUNDThermoelectric circuits may be used for cooling, heating and/or power generating applications due to the Peltier effect whereby passing a current through the junction of two different conductive materials causes a heating or cooling effect. The conductive materials suitable for thermoelectric circuits are typically rigid and relatively fragile or brittle materials.
SUMMARYAccording to one embodiment, there is provided a thermoelectric module, which comprises a base; first and second thermoelectric elements set in the base and electrically isolated by the base; and a bottom layer coupled to: a bottom surface of the base, a bottom surface of the first thermoelectric element, and a bottom surface of the second thermoelectric element, wherein the bottom layer electrically connecting the first and second thermoelectric elements.
According to another embodiment, there is provided a flexible thermoelectric circuit assembly, which comprises: a flexible circuit panel; at least two circuit conductors on the flexible circuit panel; and at least one thermoelectric module comprising a base; first and second thermoelectric elements set in the base and electrically isolated by the base; and a bottom layer coupled to: a bottom surface of the base, a bottom surface of the first thermoelectric element, and a bottom surface of the second thermoelectric element, the bottom layer electrically connecting the first and second thermoelectric elements, wherein the thermoelectric module is mounted on and connecting the at least two circuit conductors.
Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
Like reference numerals are used throughout the Figures to denote similar elements and features.
DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTSThe thermoelectric modules described herein are discrete cooling, heating and/or power generating blocks or components which may be mounted to a flexible circuit panel to create a flexible thermoelectric circuit assembly. Alternatively, the thermoelectric modules may be electrically connected with wires, adhesives, foils, etc. to create a flexible thermoelectric circuit assembly. Each thermoelectric module is rigid to protect the thermoelectric materials contained therein, but the distribution of several thermoelectric modules over a flexible circuit panel results in a flexible thermoelectric circuit assembly. The flexible circuit panel may be sized and shaped to target a specific cooling, heating and/or power generating application. The flexible circuit panel also may be configured to support suitable numbers and locations or patterns of thermoelectric modules electrically connected in series and/or in parallel to achieve the desired thermoelectric performance. For example, as shown in
The first and second thermoelectric elements 14, 16 may comprise various thermoelectric materials including but not limited to bismuth telluride (Bi2Te3), lead telluride (PbTe), or magnesium stannide (Mg2Sn). One of the two thermoelectric elements is a P-type semiconductor and the other thermoelectric element is an N-type semiconductor, as is well known in the art. For ease of reference and illustration purposes, all embodiments of the thermoelectric modules are described and illustrated herein with the first thermoelectric element 14 being a P-type semiconductor and the second thermoelectric element 16 being an N-type semiconductor.
In one embodiment, the base 12 defines first and second apertures 15,17 which receive the first and second thermoelectric elements 14, 16. The thermoelectric elements 14, 16 and apertures 15,17 in the base 12 may be generally cylindrical. In other embodiments, the base 12 may define different sizes and shapes of apertures 15,17 for receiving different sizes and shapes of thermoelectric elements 14, 16. This may include but is not limited to square, rectangular or oval apertures 15,17 in the base 12 which receive corresponding square, rectangular or oval shaped thermoelectric elements 14, 16. Alternatively, the thermoelectric module 10 may have square or rectangular cuboid thermoelectric elements 14, 16 set in round or oval apertures 15,17 in the base 12. In one embodiment, the thermoelectric elements 14, 16 are generally free-floating within the apertures 15,17. Spaces may exist within the first and second apertures 15,17 between the base 12 and the first and second thermoelectric elements 14, 16. The first and second thermoelectric elements 14, 16 may have generally the same thickness as the base 12 such that a top surface 20 of the first thermoelectric element 14 and a top surface 22 of the second thermoelectric element 16 are coplanar or nearly coplanar with a top surface 24 of the base 12. Similarly, the first and second thermoelectric elements 14, 16 have respective bottom surfaces 30, 32 which are coplanar or nearly coplanar with a bottom surface 34 of the base 12.
The thermoelectric module 10 includes a bottom layer 40 which is coupled to the base 12 and to the first and second thermoelectric elements 14, 16. Specifically, the bottom layer 40 may be coupled to the bottom surface 34 of the base 12, the bottom surface 30 of the first thermoelectric element 14, and the bottom surface 32 of the second thermoelectric element 16. The bottom layer 40 is configured to create an electrical connection between the first and second thermoelectric elements 14, 16. In some embodiments, the bottom layer 40 also serves to mechanically link or connect the base 12 and the first and second thermoelectric elements 14, 16.
In one embodiment, the bottom layer 40 is an electrically conductive material, such as a layer of copper or aluminum which may be soldered to the bottom surfaces 30, 32 of the first and second thermoelectric elements 14, 16. Alternatively, an electrically conductive adhesive may be used. Such adhesives include but are not limited to epoxies, resins or silicones, each filled with silver, copper, aluminum, or iron. The bottom layer 40 may be attached or mounted to the bottom surface 34 of the base 12 with the same adhesive used for the thermoelectric elements 14, 16 or with a different adhesive such as a structural adhesive, including but not limited to Loctite® 3616 or Epotek® H70E-4. In some embodiments, (not shown) the bottom layer 40 may be configured with areas of electrically conductive material to cover the bottom surfaces 30, 32 of the first and second thermoelectric elements 14, 16 and to electrically connect the thermoelectric elements 14, 16. The bottom layer 40 may have non-electrically conductive material in other areas of the bottom layer 40 adjacent to the bottom surface 34 of the base 12.
The flexible thermoelectric circuit assembly 50 may optionally include a dielectric layer 54 between the heat sink 52 and the thermoelectric module 10. The dielectric layer 54 is used to electrically isolate the heat sink 52 from the bottom layer 40 of the thermoelectric module 10 depending on the use or application for the flexible thermoelectric circuit assembly 50.
The flexible thermoelectric circuit assembly 50 includes a flexible circuit panel 56 which is configured with multiple circuit conductors 58 for mounting and connecting the thermoelectric modules 10. Specifically, as shown in
Returning to
The circuit conductors 58 may be layers of copper or other electrically conductive material embedded in or bonded to the flexible circuit panel 56, as is known in the art. The circuit conductors 58 may include exposed connection points (identified as “X” in
Specifically, a first link layer 78 may be coupled to the top surface 24 of the base 12 adjacent to the first aperture 74 for the first thermoelectric element 14. A second link layer 80 may be coupled to the top surface 24 of the base 12 adjacent to the second aperture 76 for the second thermoelectric element 16. The first and second link layers 78, 80 may completely or partially surround each aperture 74, 76 and/or almost completely cover the top surface 24 of the base 12, as long as some separation is provided to electrically isolate the first link layer 78 from the second link layer 80. In this embodiment, the first and second thermoelectric elements 14, 16 may have generally the same thickness as the base 12, or may be slightly taller than the base 12 such that the top surfaces 20, 22 of the first and second thermoelectric elements 14, 16 are coplanar or nearly coplanar with the top surfaces of the first and second link layers 78, 80.
A non-symmetrical layer or distinctive shape or cut-out may be provided in one or all of the link layers in order to serve as an indication for the orientation and installation of the thermoelectric module 70 on the flexible circuit panel 56. For example, the second link layer 80 shown in
When the thermoelectric module 70 is mounted to the flexible circuit panel 56, as described above and as shown in
In some embodiments, a third link layer 84 is coupled to the bottom surface 34 of the base 12. The third link layer 84 may be bonded to and cover a substantial portion or the entire the bottom surface 34 of the base 12, as shown in
The connections of the first and second link layers 78, 80 to the respective circuit conductors 58x, 58y on the flexible circuit panel 56 may result in the first and second link layers 78, 80 being electrically connected to the respective first and second thermoelectric elements 14, 16. Similarly, the connection of the third link layer 84 to the bottom layer 40 may result in the third link layer 84 being electrically connected to the first and second thermoelectric elements 14, 16. A primary function of the first, second and/or third link layers 78, 80, 84, however, is to increase the strength of the physical connections between the thermoelectric module 70 and the flexible circuit panel 56, and between the bottom layer 40 and the base 12.
In some embodiments, (not shown) the first and second TM conductors 100, 102 may be separate, isolated areas of electrically conductive material configured within a single top layer of material which covers the top surfaces 20, 22 of the first and second thermoelectric elements 14, 16. The top layer also may cover all or a portion of the top surface of the base 92 and include non-electrically conductive material in other areas of the top layer adjacent to the top surface of the base 92.
The bottom layer 98 of the thermoelectric module 90 may be attached to and cover the bottom surfaces 30, 32 of the first and second thermoelectric elements 14, 16. The bottom layer 98 also may overlap a portion or all of the bottom surface of the base 92 adjacent each thermoelectric element 14, 16 to contain or encapsulate each element. The bottom layer 98 thus may cover a substantial portion of the bottom surface of the base 92 in order to maximize the connection between the thermoelectric module 90 and heat sink 52 (not shown). Again, in some embodiments (not shown), the bottom layer 98 may also be configured as the heat sink 52.
In some embodiments, a non-symmetrical layer or distinctive shape or cut-out may be provided in one or more of the base 92, the bottom layer 98, and/or the first and second TM conductors 100, 102 in order to serve as an indication for the orientation and installation of the thermoelectric module 90 on the flexible circuit panel 56. For example, a cut-out 104 is defined by the base 92 and the bottom layer 98 in the embodiment shown in
In the embodiment of
In some embodiments, the first and second thermoelectric elements 14, 16 may have generally the same thickness as the base 92 such that top surfaces 20, 22 of the first and second thermoelectric elements 14, 16 are coplanar or nearly coplanar with a top surface of the base 92. In other embodiments, the first and second thermoelectric elements 14, 16 are slightly shorter than the outermost top and/or bottom surfaces of the base 92 to enable the first and second TM conductors 100, 102 and/or the bottom layer 98 to be partly or completely recessed within the base 92.
A further embodiment of a thermoelectric module 110 is illustrated in
It will be appreciated that different manufacturing methods and steps may be involved in producing the thermoelectric modules 10, 70, 90, 110 described herein depending on the combination of layers and conductors used. For example, if there is an integrated bottom layer 114 bonded to the base 12 as shown in
The solder and/or adhesive connections for the bottom layer 40, 98 or the integrated bottom layer 114; the first, second and third link layers 78, 80, 84 which are bonded to the base 12; and/or the first and second TM conductors 100, 102; as well as the solder and/or adhesive connections between the thermoelectric module 10, 70, 90, 110 and the circuit conductors 58 on the flexible circuit panel 56 reduces physical loading on the first and second thermoelectric elements 14, 16. By reducing the physical loading, the size of the first and second thermoelectric elements 14, 16 may be reduced while still achieving an acceptable thermoelectric performance. A reduced size of the thermoelectric elements 14, 16, and thus a reduced size of the thermoelectric module 10, 70, 90, 110, also results in reduced costs and greater flexibility for the flexible thermoelectric circuit assembly 50, 72.
It also will be appreciated that in all embodiments of the thermoelectric modules 10, 70, 90, 110 described herein, each of the bottom layers 40, 98, the integrated bottom layer 114, the first and second TM conductors 100, 102, and the first, second, and third link layers 74, 78, 84 of the thermoelectric modules, as well as the circuit conductors 58 of the flexible circuit panel 56, may be sized to achieve the required electrical conductivity, to optimize the thermal conductivity, and/or to optimize the physical connectivity of the components. The thermoelectric elements 14, 16, however, do not need to be completely covered by the bottom layers 40, 98, the integrated bottom layer 114, the first and second TM conductors 100, 102, and/or the respective circuit conductors 58 of the flexible circuit panel 56 in order to operate.
The locations of the thermoelectric modules 10, 70, 90, 110 and the connectivity created by circuit conductors 58 of the flexible circuit panel 56 may be configured to target the heating and/or cooling of a specific vehicle seat based on the size of the seat and the pressure distribution created by an occupant of the seat. Although the thermoelectric modules 10, 70, 90, 110 described herein may be used for heating and/or cooling applications by changing the current flow through the flexible thermoelectric circuit assembly 50, 72, 120, it will be appreciated that other means may exist for heating applications. Thus, in some embodiments, the thermoelectric modules 10, 70, 90, 110 and flexible thermoelectric circuit assemblies 50, 72, 120 described herein may target primarily cooling applications or applications in which heating and cooling for specific temperature control are required. In some embodiments, a resistive heating element may be combined with and/or controlled by the flexible thermoelectric circuit assembly 50, 72, 120 to provide heat more effectively. For example, a continuous loop of conductive material (not shown) may be included to add a resistive heating element to a flexible thermoelectric circuit assembly.
Alternatively, as shown in the embodiment of
In the embodiments shown in
The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described.
Claims
1. A thermoelectric module comprising:
- a base;
- first and second thermoelectric elements set in the base and electrically isolated by the base; and
- a bottom layer coupled to: a bottom surface of the base, a bottom surface of the first thermoelectric element, and a bottom surface of the second thermoelectric element, the bottom layer electrically connecting the first and second thermoelectric elements.
2. The thermoelectric module of claim 1 wherein the base defines a first aperture extending through the base for receiving the first thermoelectric element and a second aperture extending through the base for receiving the second thermoelectric element.
3. The thermoelectric module of claim 1 wherein the bottom layer comprises an electrically conductive material.
4. The thermoelectric module of claim 3 wherein the bottom layer is coupled to the bottom surfaces of the first and second thermoelectric elements by an electrically conductive adhesive or a solder connection, and wherein the bottom layer is coupled to the bottom surface of the base with an adhesive.
5. The thermoelectric module of claim 1 wherein the bottom layer covers substantially all of the bottom surface of the base, the bottom surface of the first thermoelectric element, and the bottom surface of the second thermoelectric element.
6. The thermoelectric module of claim 1 further comprising:
- a first thermoelectric module (TM) conductor adjacent a top surface of the base opposite the bottom surface of the base, the first conductor coupled to the first thermoelectric element; and
- a second TM conductor adjacent the top surface of the base, the second conductor coupled to the second thermoelectric element and electrically isolated from the first TM conductor.
7. The thermoelectric module of claim 6,
- wherein the first TM conductor comprises a layer of conductive material covering a top surface of the first thermoelectric element; and
- wherein the second TM conductor comprises a layer of conductive material covering a top surface of the second thermoelectric element and electrically isolated from the first conductor.
8. The thermoelectric module of claim 7 wherein the first conductor is affixed to the top surface of the first thermoelectric element by an electrically conductive adhesive or a solder connection; and wherein the second conductor is affixed to the top surface of the second thermoelectric element by an electrically conductive adhesive or a solder connection.
9. The thermoelectric module of claim 7 wherein the first conductor further covers a first portion of the top surface of the base surrounding the first thermoelectric element, and the second conductor further covers a second portion of the top surface of the base surrounding the second thermoelectric element.
10. The thermoelectric module of claim 1 wherein the base is molded to surround the first and second thermoelectric elements.
11. The thermoelectric module of claim 2 further comprising:
- a first link layer coupled to a top surface of the base and partially surrounding the first aperture; and
- a second link layer coupled to the top surface of the base, partially surrounding the second aperture and electrically isolated from the first link layer.
12. The thermoelectric module of claim 11 further comprising a third link layer between the bottom layer and the bottom surface of the base, the third link layer surrounding the first and second apertures.
13. The thermoelectric module of claim 12 wherein the third link layer covers substantially all of the bottom surface of the base.
14. The thermoelectric module of claim 12,
- wherein the third link layer comprises an electrically conductive material which is bonded to the base, and
- wherein the bottom layer is connected to the third link layer by a solder connection or by an electrically conductive adhesive.
15. The thermoelectric module of claim 1 wherein the base is rigid or semi-rigid.
16. The thermoelectric module of claim 1 wherein the base encloses each of the first and second thermoelectric elements.
17. The thermoelectric module of claim 1 wherein the base has a thermal conductivity substantially lower than thermal conductivities of the first and second thermoelectric elements.
18. The thermoelectric module of claim 1 wherein the first thermoelectric element comprises a P-type thermoelectric element and wherein the second thermoelectric element comprises an N-type thermoelectric element.
19. The thermoelectric module of claim 1 wherein the first and second thermoelectric elements have substantially the same thickness as the base.
20. The thermoelectric module of claim 1 wherein the bottom layer comprises a heat sink.
21. The thermoelectric module of claim 1 further comprising a heat sink coupled to the bottom layer.
22. The thermoelectric module of claim 21 further comprising a dielectric layer between the heat sink and the bottom layer.
23. The thermoelectric module of claim 21 wherein the heat sink comprises a flexible heat sink, a graphite heat sink, an extruded aluminium heat sink, or a copper heat sink.
24. A flexible thermoelectric circuit assembly comprising: at least two circuit conductors on the flexible circuit panel; and at least one thermoelectric module comprising:
- a flexible circuit panel;
- a base;
- first and second thermoelectric elements set in the base and electrically isolated by the base; and
- a bottom layer coupled to: a bottom surface of the base, a bottom surface of the first thermoelectric element, and a bottom surface of the second thermoelectric element, the bottom layer electrically connecting the first and second thermoelectric elements,
- wherein the at least one thermoelectric module is mounted on and connecting the at least two circuit conductors.
25. The flexible thermoelectric circuit assembly of claim 24 wherein the first thermoelectric element of the at least one thermoelectric module is mounted to a first circuit conductor and the second thermoelectric element of the at least one thermoelectric module is mounted to a second circuit conductor.
26. The flexible thermoelectric circuit assembly of claim 24 further comprising multiple circuit conductors and multiple thermoelectric modules, wherein each thermoelectric module is mounted to two adjacent circuit conductors to link the circuit conductors and thermoelectric modules in parallel, or in series, or in a combination of parallel and serial circuit connections.
27. The flexible thermoelectric circuit assembly of claim 24 wherein the flexible thermoelectric circuit assembly comprises a cooling thermoelectric circuit assembly for a vehicle seat.
Type: Application
Filed: Feb 8, 2018
Publication Date: Jan 9, 2020
Inventors: Jason Davis (Commerce Township, MI), Artur Stepanov (Auburn Hills, MI), Eric Kozlowski (Oakland Township, MI)
Application Number: 16/483,466